Human Cadaver Burial Depth Affects Soil Microbial and Nutrient Status
Issue: Vol 1 No. 2 (2017)
Shallow burial (c. <0.3 m) of human cadavers provides an alternative to standard burial depth (c. 1.0 m) as this can enhance the natural recycling of nutrients to the soil through improved interactions between the corpse and the soil ecosystem. However, there is a paucity of knowledge describing the interactions between the human cadaver and soil microbiology at any depth. The effects of shallow were compared to standard burial depth on soil chemical (available nitrogen and phosphorus, and organic matter) and microbial (total biomass and activity, fungal biomass, and microbial community composition) characteristics in two soil types (sandy loam and clay). Measurements were taken six and eight weeks after the burial of fresh pork ribs (used as a substitute for the human cadaver). Quantities of plant available nitrogen, as both ammonium-N (clay soil) and nitrate-N (both soil types), were greater where the pork was shallow buried. In addition, there was a shift in the composition of the bacterial component of the soil microbial community where the pork was shallow buried compared to deep burial (sandy loam soil only). There were no differences between the two burial depths (both soil types) in soil organic matter, available phosphorus, total microbial biomass or activity, or the proportion of fungi within the microbial community. The differences in available nitrogen and the lack of differences in the bacterial community composition between the two depths for the clay soils is likely to be due to reduced pore space and hence reduced oxygen at depth, which would dominate any response of the microbial community to the decomposing meat.
Author: Mark Pawlett, Jane Rickson, Joanna Niziolomski, Sophie Churchill, Michal Kešner
Benninger, L.A., D. O. Carter and S. L. Forbes. 2008. “The biochemical alteration of soil beneath a decomposing carcass.” Forensic Science International 180(2): 70–75. https://doi.org/10.1016/j.forsciint.2008.07.001
British Standards. 1995. “Soil quality: BS7755: Section 3.6: 1995. Determination of phosphorus-spectrophotometric determination of phosphorus soluble in sodium hydrogen carbonate solution.”. British Standards Institutions UK.
———. 2000. “Soil improvers and growing media: BS EN 13039:2000. Determination of organic matter content and ash”. British Standards Institutions UK.
Carter, D. O., D. Yellowlees and M. Tibbett. 2007. “Cadaver decomposition in terrestrial ecosystems.” The Science of Nature 94(1): 12–24. https://doi.org/10.1016/j.forsciint.2008.07.001
———. 2010 “Moisture can be the Dominant Environmental Parameter Governing Cadaver Decomposition in Soil.” Forensic Science International 200(1-3): 60–66. https://doi.org/10.1016/j.forsciint.2008.07.001
Fiedler, S., J. Breuer, C. M. Pusch, S. Holley, J. Wahl, J. Ingwersen and M. Graw. 2012. “Graveyards - special landfills.” Science of the Total Environment 419: 90–97. https://doi.org/10.1016/j.forsciint.2008.07.001
Finley, S. J., M. E. Benbow and G. T. Javan. 2015 “Microbial communities associated with human decomposition and their potential use as postmortem clocks.” International Journal of Legal Medicine 129(3): 623–632. https://doi.org/10.1016/j.forsciint.2008.07.001
Frostegård, Å., A. Tunlid and E. Bååth. 1991. “Microbial biomass measured as total lipid phosphate in soils of different organic content.” Journal of Microbiological Methods 14(3/12): 151–163.
Hopkins, D. W., P.E.J. Wiltshire and B. D. Turner. 2000. “Microbial characteristics of soils from graves: an investigation of soil microbiology and forensic science.” Applied Soil Ecology 14(3): 283–288. https://doi.org/10.1016/S0929-1393(00)00063-9
Pawlett, M., K. Ritz, R. Dorey, S. Rocks, J. Ramsden and J. Harris. 2013. “The impact of zero-valent iron nanoparticles upon soil microbial communities is context dependent.” Environmental Science and Pollution Research International 20(2): 1041–1049. https://doi.org/10.1016/S0929-1393(00)00063-9
Vance, E. D., P. C. Brookes and D.S. Jenkinson. 1987. “An extraction method for measuring soil microbial biomass C.” Soil Biology and Biochemistry 19(6): 703–707. https://doi.org/10.1016/S0929-1393(00)00063-9